Katy Perry performs at a campaign rally for U.S. President Barack Obama at Doolittle Park on October 24, 2012 in Las Vegas. (John Gurzinski/Getty Images)

Last night, Paul Ryan traded the campaign trail for a trick-or-treat route, celebrating Halloween with his three children, wife, sister-in-law, niece and invited members of the press in his hometown of Janesville, Wisconsin. It was a routine affair with just one exception – his daughter’s costume. Ten-year-old Liza dressed as Katy Perry, who recently performed at an Obama campaign event.

Along with Beyonce and Jay-Z, Perry is among the few pop stars taking action for Obama’s re-election, with additional support from rock icons like Bruce Springsteen. She engaged youth voters with a performance at an Obama rally in Las Vegas on October 24, where she encouraged the barely-legal members of the massive crowd to vote for the first time. On October 7th, Perry performed at an Obama fundraiser in Los Angeles, and this Saturday (Nov. 3), she’ll appear with the president at a rally in Milwaukee. “I sang for President ‪@BarackObama‬ last night because I believe in Equal Rights ‪#ForAll‬ ‪#Vote‬,” she tweeted. Additionally, Perry recently broke bread with Michelle Obama.

At her Vegas performance for Obama, Perry donned a ballot dress made out of latex – a skintight ensemble that Ryan’s name didn’t even appear on, just Mitt Romney’s.

Naturally, Ryan’s daughter didn’t wear anything near as revealing as this or Perry’s usual fashion choices, going G-rated with a rainbow outfit and a blue wig slightly reminiscent of Perry’s “California Gurls” video.

The Republican VP candidate knows a thing or two about rejection from his favorite musical acts, which he’s apparently passing along to his daughter. Earlier this year, after Ryan name-checked Rage Against the Machine as one of his favorite bands, Rage guitarist Tom Morello wrote an op-ed in Rolling Stone noting, “Paul Ryan is the embodiment of the machine our music rages against.”

Ryan opted for no costume, while his wife Janna dressed as a witch and his sons, Charlie (9) and Sam (7), were the Grim Reaper and the “Unknown Phantom,” respectively, according to the Washington Post.

No word on what Obama’s daughters, Malia (14) and Sasha (11), dressed as for Halloween, but we’re guessing it wasn’t Clint Eastwood.